1. Field of the Invention
The present invention relates to aluminum-based alloys having a high strength and a heat-resistance together with a high degree of ductility and formability.
2. Description of the Prior Art
As conventional aluminum-based alloys, there have been known various types of aluminum-based alloys such as Al--Cu, Al--Si, Al--Mg, Al--Cu--Si, Al--Cu--Mg, Al--Zn--Mg alloys, etc. These aluminum-based alloys have been extensively used in a variety of applications, such as structural materials for aircraft, cars, ships or the like; structural materials used in external portions of buildings, sash, roof, etc.; marine apparatus materials and nuclear reactor materials, etc., according to their properties.
In general, the aluminum-based alloys heretofore known have a low hardness and a low heat resistance. In recent years, attempts have been made to achieve a fine structure by rapidly solidifying aluminum-based alloys and thereby improve the mechanical properties, such as strength, and chemical properties, such as corrosion resistance, of the resulting aluminum-based alloys. However, none of the rapid solidified aluminum-based alloys known heretofore has been satisfactory in their properties, especially with regard to strength and heat resistance.
As high strength alloys, Ti alloys are generally known. However, since the known Ti alloys have a small specific strength (ratio of strength to density) because of their large density, there is the problem that they can not be used as materials for applications where light weight and high strength properties are required.